Banned terrorist outfit Tehreek-e-Taliban Pakistan (TTP) elected Usman Mansoor as their new operational chief on Wednesday after confirming the death of Umar Mansoor, the alleged mastermind of the 2014 Peshawar school attack, which killed 140 people, mostly children. Reports of Mansoor’s death had emerged in 2016 as well, which could not be confirmed.

“We confirm the death of Khalifa Umar Mansoor, and Khalifa Usman Mansoor Hafizullah will be replaced as the faction’s commander in Darra Adam Khel and Peshawar,” the Express Tribune quoted a statement from TTP.

According to reports, Umar Mansoor was wounded in a drone strike that was carried out in Paktia province of Afghanistan on Tuesday. He was then moved to an undisclosed location, but succumbed to his injuries on Wednesday.

The TTP confirmation comes a day after US carried out drone attacks on Taliban hideouts, killing 11 people on the mountainous Pakistan-Afghanistan border, following a strike a day earlier that killed 20.

According to Reuters, Mansoor got high school education in Islamabad and later studied in a madrassa. He spent some time working in Karachi as a labourer before joining the Taliban in 2007.

He was forced to take shelter in Afghanistan after the Army Public School massacre in Peshawar – the deadliest militant attack in Pakistan’s history. Mansoor had also claimed responsibility for the attack on Bacha Khan University in 2016.

Reports of his death had emerged in 2016 as well after US claimed that Mansoor was killed in an air strike in Afghanistan’s eastern Nangarhar province on July 9.